Does Deleting An Application Delete Physical Tables?

RE: Does Deleting An Application Delete Physical Tables?

Stefan Helzle — Tue, 22 Jun 2021 05:38:32 GMT

Interesting journey ;-)

One important great feature of Appian is that the platform itself will never delete or destroy any database objects. Sometimes this can be a bit annoying when I e.g. need to change the type of a field. But in the end it forces me to think about a migration plan before doing the change. While in DEV it means to simply modify the schema manually or drop and recreate.

RE: Does Deleting An Application Delete Physical Tables?

paulp0005 — Mon, 21 Jun 2021 19:00:31 GMT

Thank you, Peter Lewis!!

Your suggestions led me on a rather odd journey through the 'old' application objects and confirmed that my data was still there.

Further, it led me to the embarrassing conclusion that I merely had to click to the next page to find my tables.

Previously, my tables were on the 1st page. Then I created a new application which pushed my tables to the second page. I think I am so used to using Windows tools for managing tables that I never really saw the 'page forward feature'.

I apologize for wasting your time and that of Stefan and selvakumark.

And thank you for your help!!

Paul

RE: Does Deleting An Application Delete Physical Tables?

Peter Lewis — Mon, 21 Jun 2021 16:29:40 GMT

Keep in mind that not only should Appian not delete tables, your existing CDTs should also still exist (but not in any application). An application is just a container that facilitates deployments, but the underlying objects should still exist in the application.

If you go to the Objects view from the main page in the Appian Designer and search for your existing CDTs, do you see them there?

RE: Does Deleting An Application Delete Physical Tables?

Stefan Helzle — Sun, 20 Jun 2021 18:44:13 GMT

I try to leave schema management to Appian as much as possible. Extra stuff like views, triggers, stored procedures are separate and must be managed by you.

When creating views, keep in mind that Appian will try to create a table for them at deployment time. Add a "drop table" statement ahead of the "create view" in your DDL scripts.

If you are used to do a lot of DB stuff, then this feels odd at first.

RE: Does Deleting An Application Delete Physical Tables?

paulp0005 — Sun, 20 Jun 2021 18:38:35 GMT

Thanks for asking selvakumark. I would have taken screenshots if I thought my tables might go away. I think, really, I just deleted the application that had CDT connected to the tables.

Frankly, I am trying to rethink the whole 'my tables' thing. It seems like the possibly better way to go is to just have Appian manage your tables so you know who updated what and when (which my tables did not take into consideration). Still trying to wrap my brain around this new paradigm.

RE: Does Deleting An Application Delete Physical Tables?

Selvakumar Kumarasamy — Sun, 20 Jun 2021 11:22:34 GMT

Hi paulp0005,

As far as I know, Appian never touches the objects inside the application neither any database-related objects, if we delete the application. Could you please explain the exact steps that you followed?

RE: Does Deleting An Application Delete Physical Tables?

paulp0005 — Sat, 19 Jun 2021 21:22:50 GMT

Thanks Stefan.

I am asking where did my tables go? The fact that Appian deleted them is okay as long we as know that is what happens. There was no warning that your tables will be deleted.

Paul

RE: Does Deleting An Application Delete Physical Tables?

Stefan Helzle — Sat, 19 Jun 2021 13:46:13 GMT

In my experience, Appian is only doing non-destructive changes to DB.